It's interesting to see how the different variations evolve. Avoiding medium-large blank spaces in the middle of shotguns like this, seems to be a really painfully difficult geometric problem -- the various splitters and inserters seem to enjoy getting in each other's way. I (or someone) should probably get back to classifying the rest of the known H-to-2Gs, to get a better variety of shapes and output directions into the toolkit.

H-to-3G, H-to-4G, etc.There's another interesting line of research that I can't quite figure out how to tackle yet: suppose we have an H-to-2G already in the pattern, and a third input nearby that's in need of a particular one of the 16 classes of glider. Instead of capping the H-to-2G off with a syringe, what about just prefixing it directly with another glider-producing Herschel conduit?

If the timings and offsets of all the currently known Herschel conduits were catalogued in a way similar to the H-to-2Gs, then in a surprising number of cases we could get a third, fourth, etc., glider out of the same circuit, with only Snarks needed to make the final connections. Snarks are so much smaller and more versatile than syringes, that this ought to be a semi-significant technological improvement.

-- Or is there some better classification system in this case? The [E|O][e|o][0|1|2|3] classification is obviously pretty painfully limited to measuring the relative spacetime locations of two gliders. Maybe an arbitrarily-defined absolute frame of reference would work better for three gliders and more.

Getting back to automationIf I can stop getting distracted by other things -- which is difficult, because Calcyman's slmake is very distracting -- I might try rebuilding this shotgun using my other idea, which is really chris_c's idea from the script that automatically builds widely spaced glider salvos.

Instead of using a minimal set of 180-degree reflector components but only one splitter, I'd like to use 16 different splitters -- at which point the 180-degree turns can all just be made out of Snarks... which again will pack quite a lot tighter than all those awkward syringe-based reflectors.

dvgrn wrote:If I can stop getting distracted by other things -- which is difficult, because Calcyman's slmake is very distracting -- I might try rebuilding this shotgun using my other idea, which is really chris_c's idea from the script that automatically builds widely spaced glider salvos...

I had taken this as a "do finish the glider-to-copperhead converter, but expect a better one to be made in the not too distant future" message, and had started to build the SW shotgun. I kept on running into annoying problems (such as timing errors, edgeshooters interfering with each other, ect.), temporarily gave up in frustration, and then later came back to it again.

It is fairly small, with a bounding box of 346x345. However, it does have a large blank space in the northwest centre. I'll wait for people to make any optimizations they can find before I connect everything up to make a glider-to-copperhead converter.

dvgrn wrote:If I can stop getting distracted by other things -- which is difficult, because Calcyman's slmake is very distracting -- I might try rebuilding this shotgun using my other idea, which is really chris_c's idea from the script that automatically builds widely spaced glider salvos...

I had taken this as a "do finish the glider-to-copperhead converter, but expect a better one to be made in the not too distant future" message, and had started to build the SW shotgun....This time, I finally finished the shotgun with no problems...

Looks good! Yeah, I'm still highly distracted by slmake-related projects. So I'm not currently tempted to check other H-to-2Gs with different geometries for the two problem cases, which are the H-to-2Gs at the SW ends of the NW-side and SE-side series. They both stick out sideways, in the opposite direction from the ideal location of the inputs -- it would be better to start bringing those inputs closer together if possible.

It certainly seems as if all the easy tricks have been tried for a shotgun with these mechanisms, so it seems perfectly reasonable (as these things go) to wire up a complete shotgun.

If anyone wants to try for a more radical improvement, here's what I'd suggest:

The thing that seems to cause big empty spaces like the one in the NW-side chain is that it becomes necessary to connect a signal branch with several H-to-2Gs on it, to a signal branch with no H-to-2Gs at all. Since these salvos tend to have their final output gliders fairly close together, this inevitably means that the no-H-to-2G branch is going to need a horribly long path to delay the glider enough. Otherwise it will arrive way too soon.

One possible solution is to put an H-to-2G on every branch as soon as possible. In this case, start by connecting the SW-most two NW-side inputs with an H-to-2G, picking inserters that allow the whole mess to be packed fairly tightly against the output lanes. Then when that input is connected to the NE-most pair, there will be only a negligible amount of delaying to be done, and hopefully the input for that connection can be swung around so it's close to the axis where the next connection will be equally easy.

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That's a lot of boring words to describe a long boring process of rebuilding something that's already in good working order, though! Maybe it's just an idea for some future project. In the meantime it would be good to complete the project of classifying all the H-to-2Gs using the new script, instead of just the first third of them... that should give a much better range of geometries to solve the inevitable layout problems in this kind of situation.

Anyone is welcome to take over the classification effort, by the way. It's just a matter of copying out each candidate H-to-2G, adding eaters in various different places if it's really an H-to-3G or H-to-4G, putting in a Herschel, running the pattern, selecting the two gliders that come out, running the script and seeing what it says, and then copying the T=0 pattern into the H-to-2G toolkit stamp collection at the right place.

dvgrn wrote:Looks good! Yeah, I'm still highly distracted by slmake-related projects. So I'm not currently tempted to check other H-to-2Gs with different geometries for the two problem cases, which are the H-to-2Gs at the SW ends of the NW-side and SE-side series. They both stick out sideways, in the opposite direction from the ideal location of the inputs -- it would be better to start bringing those inputs closer together if possible.

It certainly seems as if all the easy tricks have been tried for a shotgun with these mechanisms, so it seems perfectly reasonable (as these things go) to wire up a complete shotgun.

I did not feel like making many improvements to the SW shotgun after spending so long on it, so all I did was a minor improvement by adjusting snarks. Instead, I made a large improvement on the NE shotgun. In particular, I made it so that most of the shotgun was on the SE side of the glider stream it made, rather the the NW.

After that, it did not take long to finish the stable glider-to-copperhead converter! It is fairly small — only a bit larger than the normal guns constructed by Alexey_Nigin and gmc_nxtman — and has a bounding box of 852x739.

Goldtiger997 wrote:After that, it did not take long to finish the stable glider-to-copperhead converter! It is fairly small — only a bit larger than the normal guns constructed by Alexey_Nigin and gmc_nxtman — and has a bounding box of 852x739...Is it worth filling up the empty space in the south with more snarks? There are most likely several easy ways to improve this converter that I have missed.

I'd suggest leaving it just the way it is -- it's nice to have another converter, and it's easy to make it a little smaller if there's a reason to do so later, to make a Superconducting Signal Racetrack or something. I've added a link to the first post. Progress!

Too bad we don't have a fireship tagalong synthesis that can be added from behind a moving copperhead -- (do we?) It would take quite a bit of rebuilding in the south half of this converter to make it into a G-to-fireship.

But as dvgrn mentioned in the "is this c/10 spaceship known" thread, such a converter would have a very slow repeat time. So is there any reason to build it when we could just use the pattern below which would give a faster repeat time of 375 ticks?

I've been meaning to get back and look at the old stable pseudo-Heisenburp pattern for a long time now. In particular the glider-to-2c/3-signal converter in there is incredibly ancient. I think it was built when there were only about seventeen known Herschel conduits. Now we have, what, hundreds? -- plus Snarks and syringes and so on.

With all the recent experience making converters for still life syntheses, might a cheaper way be findable nowadays, to get that 2c/3 signal going? Maybe a variant that doesn't require an initial beehive or an extra glider to repair the beginning of the wire afterwards?

Really I'm more interested in the other end of the wire, though. One of these days someone is going to dig up a faster way to get a clean signal out of a 2c/3 wire -- maybe even a direct output, with no bait still lifes to rebuild, but that might be too much to hope for. While I'm wishing I might as well wish for a fast double-to-single signal converter, to tackle the omniperiodicity problem.

Furthermore, one can move the bend by whatever distance in either direction, as long as it is eventually returned to its initial position (although successful termination then becomes much more difficult):

Extrementhusiast wrote:I had a realization about the 2c/3 diagonal signal: the basic unit is actually the half-signal, which moves the bend over by a full diagonal...So one can create a valid signal by placing a half-signal and then a diagonally-mirrored half-signal as far back as wanted.

Interesting! I wonder if that used to be generally known, and then the combined signal got optimized down to its minimum size, because nobody knew of a reason to make it longer.

I'm kind of hoping that there doesn't turn out to be a good signal turning or conversion trick that requires moving the two half-signals 20 ticks or more apart -- just because that would close off the possibility of using the new signal variant in a p19 oscillator.

Extrementhusiast wrote:Now that I've opened up that can of worms, let's get to work!

Does the five-gliders-plus-beehive signal insertion suggest any likely angles of attack, for getting a signal into the wire more cheaply?

Unfortunately, I did not realise that the repeat time of Fx119 edgeshooters is very slightly slower than the repeat time of the loafer synthesis, so it has a repeat time of 158 rather than the optimum 154:

If anyone objects to the extra four Snarks' worth of population at the bottom, it's easy to go back to a pointy lower border -- the other optimizations are still valid. Conversely, you can probably cut another few columns on the left side by adding more Snarks there. But that does start to seem silly after a while.

Goldtiger997 wrote:Unfortunately, I did not realise that the repeat time of Fx119 edgeshooters is very slightly slower than the repeat time of the loafer synthesis, so it has a repeat time of 158 rather than the optimum 154...

That Fx119 isn't terribly easy to replace, so let's just pretend nobody noticed that. I still think the next round of improvement will come when somebody gets around to digging up a seven-glider loafer recipe. Really, how can there not be a four-glider replacement for the five white gliders in this recipe?

Nobody has gotten going on three-glider enumerations with associated popseq (or hashseq) tables yet, so we don't even know for sure that there isn't a three-glider replacement. Probably the odds are against it, though. (?)

I've started work on another stable glider to spaceship converter, but I am stuck with a difficult case. I need to split a signal from the SW into the two gliders below, where the upper one has to be edgeshooted. I have found some solutions, but they are all very large and ugly, so does anyone else have any ideas?...

Goldtiger997 wrote:I've started work on another stable glider to spaceship converter, but I am stuck with a difficult case. I need to split a signal from the SW into the two gliders below, where the upper one has to be edgeshooted. I have found some solutions, but they are all very large and ugly, so does anyone else have any ideas?...

Hm, Oe3 / Oo1 classification, second glider the wrong color for NW31 /Fx119 and the geometry doesn't work anyway -- I see the problem. My idea would be to finally classify the other two-thirds of the H-to-(2)G collection and see if anything else good turns up.

Not sure when I'll get to that -- have been hoping someone else would pick up the project. It's just a matter of running the classifier script a whole bunch of times and pasting each H-to-2G into the right sub-collection. Once we have that it will be a lot easier to pick a least-worst option.

dvgrn wrote:My idea would be to finally classify the other two-thirds of the H-to-(2)G collection and see if anything else good turns up.

Not sure when I'll get to that -- have been hoping someone else would pick up the project. It's just a matter of running the classifier script a whole bunch of times and pasting each H-to-2G into the right sub-collection. Once we have that it will be a lot easier to pick a least-worst option.

Okay thanks, I had actually already thought of that, but after a long time spent browsing and searching the forum I couldn't find any link to a H-to-2G collection. Is there one that I have somehow missed, or are they just dotted around in threads like the Hunting for New Herchel Conduits?

Goldtiger997 wrote:Okay thanks, I had actually already thought of that, but after a long time spent browsing and searching the forum I couldn't find any link to a H-to-2G collection. Is there one that I have somehow missed, or are they just dotted around in threads like the Hunting for New Herchel Conduits?

They're sort of organized, but only as part of the H-to-G collection. Many of the H-to-Gs have double or triple labels, if they're really H-to-2Gs (or three different H-to-2Gs, once you go through all the combinations on a H-to-3G.)

The classifier thread mentions how far I got, but it's buried in too much other text as usual:

dvgrn wrote:I had gone through the first third of the H-to-G reference collection -- output lanes -20 to +19 ...

So pretty much anything you find with an output lane of 20 or greater, that also allows out a first natural glider, or that has some other glider output blocked off, or that is small enough that it seems worth prepending an Fx77 or an R64 or what have you (F171?) -- is still in need of classification.

It's possible that it might be worth looking at the whole classification system one more time, and see if there's some simpler alternative -- maybe that doesn't cause so much confusion when you rotate the converter 90 degrees? I don't seem to be smart enough to see any radical simplifications, and the human-compatible method of looking at the bounding box of NW and SE traveling gliders certainly seems to work okay. Better than nothing, anyway.

The best thing would be a classification system that works easily for H-to-3Gs and H-to-4Gs, so that we could occasionally get a good connection to third and fourth glider inputs, instead of being stuck all the time with glider-to-Herschel-to-two-gliders-to-two-Herschels-to-four-gliders, etc. But I'm afraid it's going to be really rare that the geometry actually works out for a H-to-4G connecting directly to four inputs, so maybe that's not worth worrying about for now.

Note that an R-pentomino is generated in the debris of the three, which could potentially be turned into a glider and then rerouted to serve as the extra! However, given its close proximity to the wire, it may be best just to delete it as is.

Extrementhusiast wrote:Note that an R-pentomino is generated in the debris of the three, which could potentially be turned into a glider and then rerouted to serve as the extra! However, given its close proximity to the wire, it may be best just to delete it as is.

Yeah, from the looks of the envelope of the incoming gliders -- blue cells above -- it's going to be tough to add catalysts to rescue that spare R, and trying to actually use that signal would probably wreak havoc with the recovery time of the circuit.

Not much point, anyway. The extra signal can be generated cheaply along with one of the synchronized gliders, with your choice of H-to-G1 converter like the one above -- in either orientation, since you can send in the cleanup glider either before or after the main reaction.

We could build a bigger H-to-G1 where the gliders would follow each other much more closely, and cut the recovery time down to something impressively small -- 62 ticks, it looks like. But that's also kind of pointless unless we can come up with a much faster way to extract signals at the other end of the wire.

Obviously we can rebuild the current 2c/3-to-glider converter, which was made with roughly Bronze Age technology. But it's going to take some new ideas along with something like a custom Bellman catalyst to restore the complex bait even as quickly as 152 ticks, when the above H-to-G1 starts working, let alone 62 ticks.

Except I didn't explain that the ship is one of simsim314's adjustable corderships. So I also made the converter adjustable. Just shift two snarks any distance to the SW as shown by the arrow, and the converter will instead create a different longer cordership (of course this will affect the repeat time).

dvgrn wrote:

Goldtiger997 wrote:I've started work on another stable glider to spaceship converter, but I am stuck with a difficult case. I need to split a signal from the SW into the two gliders below, where the upper one has to be edgeshooted. I have found some solutions, but they are all very large and ugly, so does anyone else have any ideas?...

Hm, Oe3 / Oo1 classification, second glider the wrong color for NW31 /Fx119 and the geometry doesn't work anyway -- I see the problem. My idea would be to finally classify the other two-thirds of the H-to-(2)G collection and see if anything else good turns up.

Not sure when I'll get to that -- have been hoping someone else would pick up the project. It's just a matter of running the classifier script a whole bunch of times and pasting each H-to-2G into the right sub-collection. Once we have that it will be a lot easier to pick a least-worst option.

I ended up not needing that particular signal split, because I had forgotten that for a diagonal spaceship you need a 3-sided synthesis. This meant I needed to add kickbacks, which changed the synthesis so that that particular signal split no longer existed. I did classify some of the H-to-2Gs anyway (not many though; only +20 to +26), and some of them are in the above converter.

I think this is the first case where a stable glider-to-spaceship has been built before a gun for that spaceship.

Goldtiger997 wrote:Here is the finished converter with its minimum repeat time gun of 569 ticks attached:...I think this is the first case where a stable glider-to-spaceship has been built before a gun for that spaceship.

I like it! Very nice and symmetrical, for obvious reasons. Yes, I can't think of any other cases where nobody managed to build a specific-period gun before we got around to the glider-to-spaceship. It might start happening more often if I can find the time to build an automatic compiler script that can manage a tighter packing than chris_c's script.

Goldtiger997 wrote:I did classify some of the H-to-2Gs anyway (not many though; only +20 to +26), and some of them are in the above converter.